Intestinal microbes are an important system in the human body, with significant effects on behavior. An increasing body of research indicates that intestinal microbes affect brain function and neurogenesis, including sensitivity to stress. To investigate the effects of microbial colonization on behavior, we examined behavioral changes associated with hormones and hormone receptors in the hypothalamic-pituitary-adrenal (HPA) axis under stress. We tested germ-free (GF) mice and specific pathogen-free (SPF) mice, divided into four groups. A chronic restraint stress (CRS) protocol was utilized to induce external pressure in two stress groups by restraining mice in a conical centrifuge tube for 4 h per day for 21 days. After CRS, Initially, GF restraint-stressed mice explored more time than SPF restraint-stressed mice in the center and total distance of the OFT. Moreover, the CRH, ACTH, CORT, and ALD levels in HPA axis of GF restraint-stressed mice exhibited a significantly greater increase than those of SPF restraint-stressed mice. Finally, the Crhr1 mRNA levels of GF CRS mice were increased compared with SPF CRS mice. However, the Nr3c2 mRNA levels of GF CRS mice were decreased compared with SPF CRS mice. All results revealed that SPF mice exhibited more anxiety-like behavior than GF mice under the same external stress. Moreover, we also found that GF mice exhibited significant differences in, hormones, and hormone receptors compared with SPF mice. In conclusion, Imbalances of the HPA axis caused by intestinal microbes could affect the neuroendocrine system in the brain, resulting in an anxiety-like behavioral phenotype. This study suggested that intervention into intestinal microflora may provide a new approach for treating stress-related diseases.

A ring opening polymerization method for synthesizing oligomeric poly(propylene fumarate) (PPF) provides a rapid, and scalable method of synthesizing PPF with well-defined molecular mass, molecular mass distribution (Đm), and viscosity properties suitable for 3D printing. These properties will also reduce the amount of solvent necessary to ensure sufficient flow of material during 3D printing. MALDI mass spectrometry precisely shows the end group fidelity, and size exclusion chromatography (SEC) demonstrates narrow mass distributions (<1.6) of a series of low molecular mass oligomers (700-3000 Da). The corresponding intrinsic viscosities range from 0.0288 ± 0.0009 dL/g to 0.0780 ± 0.0022 dL/g. The oligomers were printed into scaffolds via established photochemical methods and standardized ISO 10993-5 testing shows that the 3D printed materials are nontoxic to both L929 mouse fibroblasts and human mesenchymal stem cells.

The fabrication of a hierarchically structured Ni(OH)2 monolayer hollow‐sphere array with the shell composed of building blocks of nanoflakelets is demonstrated based on a colloidal monolayer and electrochemical deposition. The morphology can be easily controlled by the colloidal monolayer and deposition parameters. Importantly, such monolayer hollow‐sphere array shows a morphology‐ and size‐dependent tunable optical transmission stop band. This stop band can be easily tuned from 455–1855 nm by changing the size of the hollow spheres between 1000 and 4500 nm, and also fine‐adjusted by changing the deposition time. The array exhibits a nearly incident‐angle‐independent position of the stop band that 3D photonic crystals do not possess. This structure may have potential applications in optical devices, photonic crystals, and sensors for gas detection.

Gut microbiota has an important role in the immune system, metabolism, and digestion, and has a significant effect on the nervous system. Recent studies have revealed that abnormal gut microbiota induces abnormal behaviors, which may be associated with the hypothalamic–pituitary–adrenal (HPA) axis. Therefore, we investigated the behavioral changes in germ-free (GF) mice by behavioral tests, quantified the basal serum cortisol levels, and examined glucocorticoid receptor pathway genes in hippocampus using microarray analysis followed by real-time PCR validation, to explore the molecular mechanisms by which the gut microbiota influences the host’s behaviors and brain function. Moreover, we quantified the basal serum cortisol levels and validated the differential genes in an Escherichia coli-derived lipopolysaccharide (LPS) treatment mouse model and fecal “depression microbiota” transplantation mouse model by real-time PCR. We found that GF mice showed antianxiety- and antidepressant-like behaviors, whereas E. coli LPS-treated mice showed antidepressant-like behavior, but did not show antianxiety-like behavior. However, “depression microbiota” recipient mice exhibited anxiety- and depressive-like behaviors. In addition, six glucocorticoid receptor pathway genes (Slc22a5, Aqp1, Stat5a, Ampd3, Plekhf1, and Cyb561) were upregulated in GF mice, and of these only two (Stat5a and Ampd3) were upregulated in LPS-treated mice, whereas the shared gene, Stat5a, was downregulated in “depression microbiota” recipient mice. Furthermore, basal serum cortisol levels were decreased in E. coli LPS-treated mice but not in GF mice and “depression microbiota” recipient mice. These results indicated that the gut microbiota may lead to behavioral abnormalities in mice through the downstream pathway of the glucocorticoid receptor. Herein, we proposed a new insight into the molecular mechanisms by which gut microbiota influence depressive-like behavior.

Complex three-dimensional (3D) pore geometries, useful for tissue engineering scaffolds, can be fabricated via photo-crosslinking of resorbable poly(propylene fumarate) (PPF) resins using stereolithography (SLA) and/or continuous digital light processing (cDLP) methods. Physico-chemical parameters inherent to 3D printable resin design, include viscosity, polymer concentration, degree of polymerization, and resin printing temperature. We report here on our study of these parameters and their influence the cDLP 3D printing process and the resulting mechanical properties. A series of PPF oligomers were synthesized by the ring-opening copolymerization (ROCOP) of maleic anhydride and propylene oxide followed by a base-catalyzed isomerization. The resin viscosities were measured as a function of number-average molecular mass ( M n ) of the PPF oligomers (1.1, 1.7 and 2.0 kDa), concentrations of PPF in the reactive diluent diethyl fumarate (DEF) (50 and 75 wt %) and resin temperature (25 to 55 °C). The zero-shear viscosity (η 0 ) of the resins was found to be temperature-dependent and follow a linear Arrhenius relationship. Tensile tests demonstrated mechanical properties within the range of trabecular bone, with the ultimate strength at break above 15 MPa and elastic moduli between 178 and 199 MPa.

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The authors report the fabrication of gold flowerlike nanoarchitectures (FNs) on indium tin oxide coated glass substrate using a low-cost electrochemical strategy at a proper current density and polyvinylpyrrolidone concentration in electrolyte. The FNs are grown and built with the blocks of two-dimensional flakelike nanostructures. Importantly, such FNs show strong surface-enhanced Raman scattering (SERS) effect associated with their geometries, which is much stronger than that from other particle films. The minimum concentration of detectable rhodamine 6G molecules can be down to 10−12M. These FNs with strong SERS effect could be used in chemical analysis, biosensors, and nanodevices with molecule-level detection.

The mesoporous TiO(2) solid and hollow spheres have been synthesized via a controllable and simple chemical route. Structural characterization indicates that these TiO(2) mesoporous spheres after calcined at 500 degrees C have an obvious mesoporous structure with the diameters of 200-300 nm for solid spheres and 200-500 nm for hollow spheres. The average pore sizes and BET surface areas of the mesoporous TiO(2) solid and hollow spheres are 6.8, 7.0 nm and 162, 90 m(2)/g, respectively. Optical adsorption investigation shows that TiO(2) solid and hollow spheres possess a direct band gap structure with the optical band gap of 3.68 and 3.75 eV, respectively. A possible formation mechanism for TiO(2) solid and hollow spheres is discussed.